Crush Mistake?

[PhillyDave]

Hey everyone, I've been lurking for months and learning a lot, but I have question. My last brew's wort SG came out to 1.042, but my recipe through beersmith expected 1.056. I also had too much wort post boil was looking for 5.5gal, but had closer to 6.5 or 7. I hit the beersmith mash and sparge temps and volumes. This makes me think the grain crush was inadequate. I think this because it seems logical : if not crushed properly, efficiency suffers and, presumably, absorption as well. What do you guys think? Are there other possible culprits here?

 

[DocScott]

Your volumes are off, that's why your gravity is less. Gravity is basically a density calculation: mass/volume. It sounds like you added too much water either during infusion or sparge and did not boil down enough to reduce your volume to the amount (5.5 gallons) your recipe (and therefore expected OG) was calculated for. Nothing you can do for it now, but next time watch your volumes and you should hit your gravity better.

 

[PhillyDave]

Ok, so are you saying undercrushed grain does not result in less absorption? I knew the issue had to be pre-boil, because my pre-boil SG was 1.034 (Beersmith estimated 1.042). To me this said it was either water volume or crush, because I clearly didn't get the sugars from the grains I was looking for.

Thanks for the response.

 

[twistr25]

Theoretically if the water can't get through the hull it won't be absorbed, so yes, but I would think you'd have to miss quite a bit for that to be noticeable. Looks like you didn't boil off enough. How much did you start your boil with? Do you leave the lid on during the boil? As Doc said, the more volume, the more dilute the sugars will be, so it will show a lower gravity.

 

[BryceL]

My first guess would be that the main factor is your volumes. It could also be your crush, but with your volumes being off there isn't really a way to tell which is causing your gravity to be low. Off by 1 - 1.5 gallons is quite a bit, that's why I'm assuming this is your problem. Did you get a good boil going?

 

[PhillyDave]

I did get a fair rolling boil going, but I thought it was less vigorous than normal. I think you are right that the volumes are the real culprit, and I think I know where it went wrong. My brew buddy measured the sparge, 4.9 gal, and we heated it up to 168. When I went to transfer it to our HLT (a 5 gallon Igloo watercooler), it didn't fit. I can't offer an intelligent explanation now, but for some reason I just figured the cooler was undersized and wrote off the issue. I transferred the water in the HLT back into the pot and kept it at 168, drained the mash, and then sparged. So I think the sparge was measured incorrectly.

 

[dmob29]

Sounds like you pretty much got it figured out, but I wanted to offer a tip that I practice.
I don't really use exact calculations when I sparge/lauter as I have a 10 gal MLT cooler and use as much sparge water as needed to get to my boil volume. Whether I am planning to boil for an hour I will collect 6.5-7 gals as I boil off about a gal/hr or boil for 2-3 hrs for a big beer to collect all those sugars and will collect 8-9 gals. The point is that I measure as I collect into my boil kettle, and also measure a couple times during the boil to make sure my boil off is going as thought.
The more you brew you will figure out your systems boil off rate. This works for me so I thought I'd share. Hope it helps.

 

[sketerbuck]

My first guess would be that the main factor is your volumes. It could also be your crush, but with your volumes being off there isn't really a way to tell which is causing your gravity to be low. Off by 1 - 1.5 gallons is quite a bit, that's why I'm assuming this is your problem. Did you get a good boil going?

The problem is your volume. 5.5 gallons x 56 (1.056) divided by 7 ( the volume you got ) equals 44 ( 1.044 ). Very close to what you got.

 

[menerdari]

I agree, Volume is the issue, and if you haven't done it already, measure your boil off rate and then you will know how much pre-boil wort you need to reach your final amount.
ie... my turkey fryer boils off a little over 1 gal/hour, my stove is 1/2 gal/hour. so I adjust my mash calculations to fit.

 

[zeg]

In addition to the above, you need to check all your volume losses. BeerSmith accounts not only for absorption and boil-off, but also for losses at each transfer. If you're expecting to lose half a gallon to mash tun dead space and another half gallon to kettle dead space, that could be the difference there. You need to measure and adjust these to get more accurate predictions down the road.

Or, just boil longer to reduce volumes. That isn't ideal, though.